Exposing seedlings of the flax, Linum usitatissimum L., to a variety of weak
environmental stresses followed by a 2 day calcium deprivation, triggers the
common response of production of epidermal meristems (actively dividing
groups of cells) in the hypocotyl, which is the part of the stem between the
root and the cotyledons (the pre-existing leaves in the embryo). This
production reaches a plateau of 10-20 meristems after a month in the case of
mechanical stimulation and cold shock.

Recently, we have shown that
radiation from a global system for mobile communication (GSM) telephone also
triggers production of meristems with a plateau of around six meristems.

Here, we show that a single 2 h exposure to radiation emitted at 105 GHz at
non-thermal levels by a Gunn oscillator induces meristem production with
kinetics similar to that induced by weak environmental stimuli and radiation
from GSM telephone.